Contact attachment for electrical connections



June 4, 1940.

Filed Dec. 24, 1935 INVENTOR ATTORNEY Patented June 4, 1940 PATENT. oFF-ic-E CONTACT ATTACHMENT FOR ELECTRICAL CONNECTIONS Alfred J..A ndersn, Akron, Ohio Application December 24, 1935, Serial No. 56,001

I .8 Claims. (01. 173-36l) I the socket member of theconnection and illus- This invention relates to plug-in connections for electrical circuits and has particular relation to a contact attachment interposable between the co-operating contact members of such plug-in connections.

" This application is a continuation in part of an application filed by this applicant, February 26, 1935, Serial Number 8,394.

It is well known that it is difficult to secure a my perfect contact between the co-operating contact members of a plug-in connection. In some connections a fairly good contact is pro-vided while the connectionis comparatively new, but even in plugs of the most improved construction [5,; the contacting members soon become loosened,

bent or worn to an extent which will cause a loose or arcing contact which is very objectionable to radio reception and which is very inefficient and unreliable.

30d Objects of the invention are to provide. simple,

inexpensive means which can be quickly and conveniently interposed between the contacting members of a plug-in connection to provide a perfect contact there'between.

A further object is to provide a member of the character above indicated which will frictionally engage the cooperating parts to more firmly hold the same in operative relation against unintentional detachment.

m An additional object is to provide a Contact spring of the character above indicated having means for detachably securing it in an, operative position on a prong of a plug connection, whereby the same will be retained on a prong and will not become dislodged when the operating parts are separated. v

The above objects are accomplished and additional ends are attained by the novel construction, combination and arrangement of parts here'- (L inafter described with reference to the accompanying drawing in which there is shown an illus-. trative embodiment of the invention, it being understood that changes and modifications may be made or resort had to substitutions which come within the spirit of the invention asset forth in the claims hereunto appended.

In the drawing: Figure l is a side elevational view of a contact spring constructed in accordance with this invention, I Figure 2 is an elevational view of the outwardly presented side of same,

Figure 3 is a similar, elevational viewshowing the inner side of same, Figure 4 is an elevational View of one of the members of a plug-in connection having contact springs constructed in accordance with this invention operatively positioned thereon.

Figure 5 is a similar view of a plug-in connec- Dd tion showing the same operatively positioned in Proceeding now to a detailed description of the invention with reference to the particular adaptation thereof disclosed in the drawing, the numeral 8 denotes the plug member of an electrical connection and the numeral 9 denotes the socket member of such connection. The parts 8 and 9 as shown in the drawing are of ordinary construction, it being understood that the invention is applicable to any form of connection to which it may be advantageously applied.

The plug portion 8 of the connection is provided with the usual prongs l0 and 'H and each prong is provided with the usual opening or indentation l2, which is formed therein adjacent the free end thereof. The socket member 9 is provided with the usual contact members 53 and M which are operatively positioned within the I sockets l5 and I6 which are formed therein to receive the prongs I0 and l I. A contacting member l1 constructed in accordance with this invention iscomposed of a relatively thin strip of electrically conductive material preferably phosphor bronze. .The strip is provided at the basev end thereof with laterally projecting tabs I8 and H) which are bent forwardly then inwardly with the free ends thereof positioned in the same plane to provide means for securing the strip ll to one of the prongs H] or I l. The strip l! is bent upon itself to form an open sided loop with the portion 2| of the loop disposed at a slight angle to the base portion 2i! and with the free end 22 of the strip terminating in close, spaced relation to the portion 2!. The portions 2! and 22 are of approximately the same length, the base portion extending beyond these portions whereby the portion 22 maybe forced inwardly against the portion 2| without contacting with the tabs I8 or I9. I

The portion 2| is provided on the inwardly presented side thereof with a protuberance 23 which is preferably formed therein by making the indentation 24 on the outwardly presented side thereof but which may be formed thereon in any suitablemanner. The portion 22 is provided directly opposite the protuberance 23 with an opening 25 the purpose of which will be here inafter described.

In the particular adaptation of the invention illustrated in Figure 6, each contact spring i1 is shown with the opening 25 omitted from the free end portion 22. The opening 2.5 is necessary only when the protuberance projects through the usual opening i2 in the prongs II and I2 to an extent which will interfere with the spring action of the end portion 22.

In use, the contact spring I! is positioned on one of the prongs H1 or H by entering the free end of the prong between the tabs l8 and I9 and the base portion 20, and the spring i1 is forced downwardly on the prong. As the base portion is positioned at an angle to the portion 2iv the free end of the prong H3 or M will first contact with the portion '22 of the loop from which position it may be forced on the prong with the prong received in the extreme end of the loop as disclosed in the drawing. In this position the protuberance 23 is seated in the opening I2 to retain the contact member 11 in position on the prong. While the contact spring I! is positioned on one of the prongs i9 and H as shown in the drawing the portion 22 will be forced by the wall of one of the sockets E5 or l6'against the inner side of the prong it] or IE on which it is thus secured. This distortion of the portion 22 causes a slight outward bulge in the portion 2!, thus forming a spring pressure contact between the co-operating members of the plug-in connection.

If desired the contacting member herein disclosed may be oppositely positioned on the prongs Hi and H with the portions 22 presented outwardly in which case the opening will serve the ordinary function of the indentation 24 or the openings I2.

While I have illustrated and described a contact spring I! provided with tabs l8 and E9, the protuberances 23 and the opening 25, it will be understood that any equivalent means may be employed and that one or more of the features may be omitted and the open sided loop used without these features to considerable advantage.

It will also be understood that while I have shown a. contact spring l7 applied to the prongs ill or II of the member 8 that the open. sided loop I! may be inserted in one of the sockets IE or N3 of the member 9.

It will be seen that I have provided a contacting member of simple, inexpensive construction which may be quickly and conveniently placed in an operative position on a prong and which will be held thereon by the tabs IE or 19 and by the protuberance 24 against unintentional displacement.

Having thus illustrated my invention and described the same in detail, what I claim as new and desire to secure by Letters Patent is:

1. A spring contact attachment interposable between a prong and the co-operating contacting member of a plug-in connecting for an electrical circuit, comprising a flat strip bent upon itself to form an open sided loop for receiving said prong when positioned longitudinally thereon and a protuberance on said strip, said protuberance positioned to be entered in the usual aperture in the extremity of said prong to detachably hold the same in an operative position thereon.

2. A spring contact attachment interposable to detachably hold the attachment" in an operative position thereon.

3. A spring contact attachment interposable between a prong and 'co-operating contacting member of a plug-in connection for an electrical circuit, comprising a flat strip of metal bent upon itself to" form a flat, open-sided loop for receiving a prong; means on one end of said strip for engaging the base portion of said prong and means on said strip for engaging the prong adjacent the end thereof; both of said means co-operating. to detachably secure said attachment in alongitudinal position on said prong enter in the usual aperture in the extremity of a prong.

5. A spring contact attachment for a prong of a plug-in connection comprising a strip of metal approximately equal in width tothe prong, one end portion of said strip forming a body having means at one end whereby it may be engaged with the prong; the opposite end of the strip being bent upon itself to provide a returned end for embracing the extremity of the prong, this returned end being resilient and free from attachment to the body of the strip,

said strip having an indentation on one side thereof forming a protuberance on the other side thereof for entering the usual aperture in the extremity of the prong.

6. A spring contact attachment for a prong of a plug-in connection comprising a strip of metal approximately equal in width to the prong and having means at one end whereby it may be engaged with the prong; the opposite end of the strip being bent upon itself to embrace the ex tremity of the prong; this returned end being resilient and free from attachment to the body of the strip; the body of the strip having a protuberance adapted to enter the usual aperture in the extremity of the prong, the free end of the strip provided with an opening which coincides with said protuberance.

'I. A spring contact attachment interposable between a prong and a co -operating contacting member of a plug-in connection for an electric circuit; said attachment comprising a strip of substantially the same width as the prong, bent upon itself to form any open sided loop adapted to receive the prong and means on one end of said strip for holding the loop in a longitudinal position on said prong.

8. A spring contact attachment interposable between a prong and a co-operating, contacting member of a plug-in connection for an. electric circuit; said attachment comprising a strip of.

ALFRED J. ANDERSON. 

